Monday, July 20, 2009

Tom DeMarco on Software Engineering

Software development is inherently different from a natural science such as physics, and its metrics are accordingly much less precise in capturing the things they set out to describe....Strict control is something that matters a lot on relatively useless projects and much less on useful projects. It suggests that the more you focus on control, the more likely you’re working on a project that’s striving to deliver something of relatively minor value.To my mind, the question that’s much more important than how to control a software project is, why on earth are we doing so many projects that deliver such marginal value?...So, how do you manage a project without controlling it? Well, you manage the people and control the time and money. You say to your team leads, for example, “I have a finish date in mind, and I’m not even going to share it with you. When I come in one day and tell you the project will end in one week, you have to be ready to package up and deliver what you’ve got as the final product. Your job is to go about the project incrementally, adding pieces to the whole in the order of their relative value, and doing integration and documentation and acceptance testing incrementally as you go.”...For the past 40 years we’ve tortured ourselves over our inability to finish a software project on time and on budget. But this never should have been the supreme goal. The more important goal is transformation, creating software that changes the world or that transforms a company or how it does business.